NTSB Safety Recommendation Letter P-77-021 through P-77-023

Page 1Official PDFWASHINGTON, D.C. I S S U E D : September 9 , 1977 Forwarded to: Nr. Edward L. Patton Chairman SAFFTY RECOMMENDAT I ON About 3 : 4 5 p.m. Anchorage T i m e , J u l y 8, 1977, an explosion and f i r e ccurred a t Alyeska Pipeline Service Company's (Alyeska) Pump S t a t i o n 0. 8 on t h e Trans-Alaska pipeline. A s a r e s u l t of t h s accident one son died and f i v e persons were injured. The National Transportation Safety Board's ongoing i n v e s t i g a t i o n ndicates t h a t t h e explosion a t Pump S t a t i o n No. 8 occurred when crude il w a s turned i n t o Pump No. 1 w h i l e t h e workers were servicing t h e ump's s t r a i n e r . The o i l under a pressure of about 4 0 0 psig sprayed out f the open cover and rapidly f i l l e d the building w i t h vaporized crude o i l . The vapor w a s i g n i t e d by one of s e v e r a l possible sources and exploded. The f o r c e of t h e explosion heavily damaged t h e building and the gushing crude o i l was i g n i t e d ; t h e s t a t i o n was shut down and i s o l a t e d from the e l i n e within minutes. The damage t o t h e environment w a s minimal, but pump s t a t i o n was p r a c t i c a l l y destroyed. lnformation obtained a f t e r i n t e r r o g a t i n g personnel d i r e c t l y affected by t h i s accident revealed t h a t before removing and cleaning the No. 1 pump's s t r a i n e r , t h e s e l e c t o r switch f o r t h e No. 1 pump suction valve's motor operator had been placed i n the manual position t o allow t h e men i n t h e pump room t o c l o s e t h i s valve and then d r a i n t h e crude o i l out of t h e s t r a i n e r . However, a f t e r t h e valve was closed t h e c o n t r o l f o r t h e a l v e operator w a s not "locked out" e l e c t r i c a l l y t o render t h e No. 1 ump s u c t i o n valve inoperative as the Alyeska company procedures d i r e c t . a t e r , while the men i n t h e pump room were opening t h e s t r a i n e r , the e l e c t o r switch was repositioned from the manual position t o t h e automatic o s i t i o n . This a c t i o n caused t h e suction valve t o begin t o open allowing t h e crude o i l stream t o e n t e r t h e p a r t i a l l y opened s t r a i n e r . 2145-B - A n - 7 4 - 3#

Page 2-2- Although the men i n the pump room immediately saw t h e crude o i l e n t e r t h e s t r a i n e r and would have had time t o s t o p it, they were unable t o do s o because the pump suction valve could not be operated from t h e pump room when its s e l e c t o r switch was i n t h e automatic position. Additional testimony revealed t h a t i n t h e ensuing confusion caused by t h e now s p r a y i n g and vaporizing crude o i l , t h e men i n t h e pump room radioed t h e pump s t a t i o n control room t o s h u t down, but they d i d not specify t h e No. 1 pump. The pump s t a t i o n c o n t r o l room personnel were unable t o see i n t o any p a r t of t h e pump room because the pump room w a s completely enclosed a s a protection a g a i n s t the A r c t i c weather con- d i t i o n s . Therefore, they were not aware of t h e No. 1 pump s u c t i o n valve opening and they complied w i t h t h e order t o shut down by s h u t t i n g down No. 2 which was running a t t h e t i m e . The pump s t a t i o n design is such t h a t n e i t h e r the pump room nor t h e t u r b i n e room is v i s i b l e from the pump s t a t i o n c o n t r o l room. Therefore, because of the i n a b i l i t y t o c o n t r o l the valves o r t o shut down t h e pumps from t h e pump room, and because of t h e i n a b i l i t y of personnel i n the pump s t a t i o n control room t o monitor operations v i s u a l l y i n t h e pump room and turbine room, t h e National Transportation Safety Board recommends t h a t t h e Alyeslca P i p e l i n e Service Company: I n s t a l l a c o n t r o l i n t h e pump room t o shut down t h e pumps from t h a t location. (Class I, Urgent Followup) (P-77-21) I n s t a l l a c o n t r o l i n the pump room t o operate t h e pump valves from t h a t l o c a t i o n a t any t i m e . (Class I, Urgent Followup) (P-77-22) I n s t a l l a closed c i r c u i t - t y p e video camera i n t h e pump room and turbine room t o allow t h e pump s t a t i o n c o n t r o l c e n t e r t o monitor v i s u a l l y a l l a c t i v i t i e s at these locations. (Class I, Urgent Followup) (P-77-23) TODD, Chairman, BAILEY, Vice Chairman, McADAMS and HOGm, Members, concurred i n t h e above recommendations. HALEY, Member, d i d n o t p a r t i c i p a t e . 4 Acting Chairman#